“Alzheimer’s disease (AD) is our #1 public health problem in terms of cost and burden of care and it is projected that over 100 million people will be diagnosed with Alzheimer’s worldwide by 2050,” said Stephen Salloway, MD, MS, a professor of Neurology and Psychiatry at Brown University and the Institute on Aging (IOA) at the University of Pennsylvania’s most recent Visiting Scholar.
On Tuesday, November 15, 2016, Dr. Salloway visited the University of Pennsylvania to present a lecture on “Developing Breakthrough Treatments for Alzheimer’s Disease” in which he shared some of the latest advances, and challenges, in the field of Alzheimer’s disease research.
“Our goal, and the goal of the National Plan developed by the U.S. Congress, is to develop breakthrough treatments by 2025.” – Stephen Salloway, MD, MS
It’s no secret that the world is getting older. In fact, according to Dr. Salloway, there are many regions of the world where more than 30 percent of the population will be 60 or older and coming into the risk state for cognitive impairment. Aside from the staggering and rising cost of care for Alzheimer’s disease and related dementias, it is the disease that older people fear most — fearing the disability and loss of identity.
With this in mind, you would assume that Alzheimer’s research would be a top priority, but “funding for Alzheimer’s disease at a federal level has paled in comparison to other diseases like cancer and heart disease,” said Dr. Salloway. However, things are starting to look up and we have recently started to see some improvement. For the first time, there is a strong potential for Alzheimer’s federal research funding to reach over $1 billion.
Researchers are steadily working to build a worldwide infrastructure to fight Alzheimer’s disease with a number of private/public partnerships, collaborative initiatives such as the Alzheimer’s Disease Neuroimaging Initiative (ADNI) one component of which is right here at Penn, and many other alliances across the board. We’ve already seen several important benefits emerge from these initiatives; for example, real time data sharing to trigger an increase in publications and shape new trials and views on Alzheimer’s research.
Several advances in AD research have been made over the years, from the discovery of plaques and tangles to the development of new imaging techniques and biomarker breakthroughs. “We now know that plaques and tangles begin accumulating 15-20 years before the onset of cognitive decline,” explained Dr. Salloway. Through these findings, we are able to better understand the progression of Alzheimer’s disease as a process starting with a long pre-clinical period, moving on to an early symptomatic period of mild cognitive impairment (MCI), then followed by the actual dementia period. The significance of understanding this process is that it opens the door of opportunity to eventually intervene before a patient reaches the late stage of Alzheimer’s disease.
In terms of current treatments, there are two classes of medications approved to treat the symptoms of the dementia phase of Alzheimer’s disease—cholinesterase inhibitors and memantine. Both drugs have been found to have a very mild multi-symptomatic clinical effect, but cannot cure the disease or stop it from progressing, which is the ultimate aim for researchers.
Since 2003, there have been no new treatments approved by the U.S. Food and Drug Administration (FDA), but there have been several clinical trials focusing on the amyloid pathway — some disappointing and some encouraging.
Two major phase-3 trials were the bapineuzumab trial and the solanuzumab trial. While the bapineuzumab trial was stopped after showing no clinical benefit, the solanuzumab trial raised some hope after findings showed some modest slowing of cognitive decline in a milder subgroup. We are expecting to see some new results soon from a replication trial.
Most recently, some very encouraging results emerged from a phase 1b trial focusing on the antibody, aducanumab. This study showed a substantial dose-dependent lowering of a-beta on amyloid PET scans and also suggested dose-dependent lowering of cognitive decline. There are currently two phase-3 trials underway hoping to reproduce these findings in early Alzheimer’s disease.
“This is very exciting to enter the era of Alzheimer’s prevention, but there are many challenges,” said Dr. Salloway. One of the biggest challenges that researchers face is recruitment of a much larger sample size and population than they’ve used in the past. “In the past, we have tested medicine for people who are cognitively impaired, mostly with dementia, and now we have to reach people who may be at risk for Alzheimer’s in a community who is not coming specifically for care,” he explained. This means they will need hundreds of thousands, if not millions, of people to be enrolled in order to find the highest group at risk and to test medications.
For Dr. Salloway, trying to figure out how to reach and engage this community “is a vastly new undertaking and a second career.” However, he believes that a big avenue is going to be through all types of media—social media, print media, broadcast media, etc.
“The media is critical for getting the word out” – Dr. Salloway
Following the publication and coverage of the results of the aducanumab trial, Dr. Salloway’s center had over 500 calls from people looking to volunteer for research.
In terms of future research, Dr. Salloway has a vision. Through the eventual use of combination treatments and therapies, “Alzheimer’s disease will be much more treatable and manageable than it is today,” he believes.
“Our goal is to detect risk, initiate treatments early, engage the public, develop new public/private partnerships, and to make investments in research to succeed [in fighting Alzheimer’s disease].” – Dr. Salloway
Dr. Salloway is also the Director of Butler Hospital’s Memory and Aging Center.